Oil temp / pressure at a trackday

[james fillingham]

I was whizzing around Goodwood yesterday and was keeping a keen eye on my oil. After c.6/7 laps of fairly rapid (for me) progress, much at or near the limiter, my oil temp was just short of the red mark (ie hot) and my oil pressure dropped to the low mark. I stopped soon thereafter!

 

I am used to the temp rising and the pressure falling, but I haven't seen the pressure falling to near the red bit when at high revs, usually only at idle. Do people think this a fuction of Goodwood being a fast circuit or something I should look at (and if so what / how)?

 

Will be interesting to compare findings at Lydden this weekend. Only problem will be my feelings of inadequacy (driving skills!) are likely to increase on a track with you chaps. Yesterday I was the only Caterham on track!

[Peter Carmichael]

The oil pressure issue should be nothing to do with the revs but everything to do with cornering. You have not described your car, but is it a K series? Does it have the Apollo tank?

[james fillingham]

It's a regular 1.6k supersport from 1998 with an Apollo tank (recently fitted as an upgrade!). I didn't notice the dipping in pressure only on/after corners, but that could be my lack of observation rather than what was actually happening. It also definitely seemed to get lower as I got further into a session.

[MikeE]

James,

 

I recently fitted an Appollo to my 1.6SS and am using the existing water temperature guage for the oil temp as well. I took the car to a trackday in France a couple of weeks back and noticed that the water temp was running high but seemed OK (approaching 100 I guess) but when I switched to the oil temp this was running very high (around 120). Now I'm not sure but I do question the accuracy of the oil temp sender, maybe it's just way off the mark? Having said that my oil pressure still remained normal.

 

BTW I'm off to Lydden on Saturday (and am in the novice group) and am based in Fleet - we could form a two car convoy

 

Mike

[Peter Carmichael]

If you have just fitted an Apollo, you have an oil temp sender (attached to a worry gauge) for the first time. This will show up unmanaged oil temperatures under track use and shows that some form of oil cooling is a good idea.

 

James,

 

First thing to check is the pressure sender as these are notoriously faulty and will give undue worry. With an Apollo fitted, you get to see the high temperatures that crank windage gives. These high temperatures should not give rise to any drop in pressure at running rpms. You might also have a low oil level. Are you correctly checking oil level with the engine running and with the correct dipstick?

[MikeE]

ust a thought but....is there any way of independently measuring the oil temperature (for example sticker a temperature gauge down into the sump (or into the top of the appollo tank) following a good thrashing? If so would anyone going to Lydden be able to lend me a hand to check my (and James') oil temperature?

 

BTW Surel the apollo tank would help to dissipate heat (acting as a radiator, that and you've got an extra 3 litres of oil in the system)?

 

Mike.

 

 

[Peter Carmichael]

How much surface area does an Apollo tank have? Does it have fins and ridges? Its cooling effect is negligible.

 

The extra volume only slows down the change in bulk oil temperature. It does not affect the equilibrium temperature.

 

Dry sumped Ks seem to be much more tolerant of track abuse and maintain their temperatures very well without necessarily fitting an oil cooler. This is probably down to their not suffering from windage in the same way as the wet sumped engines.

 

Edited by - Peter Carmichael on 26 Sep 2002 12:51:13

[scooby dooby doo]

you can get heat sensitive stickers - they change colour (permanantly) if a certain temperature is exceeded.

 

HOOPY R706KGU what's a 'hood' 🤔 😬

[james fillingham]

Interested in comment about oil levels / checking. I know this sounds rather basic, but when the oil is hot and very clean (a good thing) I find it difficult to check levels on the standard dipstick. I reckon it's OK when I hold it to the light and do lots of wiping/waving. Are there any other ways of telling or modified dipsticks that will give me a warmer feeling? I take some comfort from the absence of oil on the garage floor or around the engine bay and the fact there is a normal level of pressure on start-up / normal revs.

 

I am very happy to get some more expert help on temps / pressures / cunning measurement techniques and second opinions at Lydden.

[MikeE]

OK fair enough (although I think you missed the word 'significantly' from your statement about equalibrium 😬), so is an (indicated) oil temperature of 115 critically high? (given that the indicated oil pressure appeared to be fine)